Metal-working machine.



J. R. `& T. R. CRLLIN.

METAL WORKING MACHINE.

l APPLICATION FILED NOV. 23,1911.

Patented sept. 29, 1914.

8 SHEETS-SHEET 1.

J. R. da T. R. CRELLIN, METAL WORKING MACHINE.

APPLICATION FILED 11011.23, 1911.

1,112,269, ,1 Patented s941129, 1914.

8 SHEETS-SHEET 2.

J. R. & T. R. .GRELLI'N METAL WORKING MACHINE.

APPLICATION FILED NOV. 23. 1911. I

Patented Sept. 29, 1914;

8 SHEETS-SHEET 3.

METAL WGRKIN G MACHINE.

A1 1 0u 1 nvy 2 Lb' nu.. e S d e t n na. P m no V. 0 N D E T.. ,l P N 0 I T A G I L D.. P A

SHEETS-SHEET 4.

www@

lik

J. R. & T. R. CRELLIN. METAL WORKING MACHINE.

APPLICATION FILED NOV. 23,1911.

Patented 861013.29, 1914.

8 SHEETS-SHEET 5.

J. R. e T. R. GRELLIN.

METAL WORKING MACHINE.

APPLICATION FILED NOV. 23, 1911.

1 1 1 2,269, Patented Sept. 29, 1914.

8 SHEETS-SHEET 6.

J. R. & 'I'. R. CRELLIN. METAL WORKING MACHINE.

APPLICATION FILED Nov. 23, 1911,

Patented Sept. 29, 1914.

8 SHEETS-SHEET 7.

I'illllll J. R. & T. R. CRBLLIN.

METAL WORKING MACHINE.

APPLIGATION FILED 110123.11911.

Patented Sept. 29, 1914.

8 SHEETS-SHEET 8.

l UNITED sil-#Aires 'PA-critter OFFICE.

JAMES R. RELLIN 'NDJTHOMAS iR. CRELLIN, OF iPHTLADLPHIA, PENNSYLVANIA METALWIRKING v'Specification ofLett'ers latent.

ppm-'anon mea Novemherm, 19.1.1. `serial No. sensa?.

Be it known that we, JAMES R. CRELLIN and. THOMAS R. CnnnmN, lbeth citizens of `the United Statesnend residents of Mount Airy, Philadelphia, Pennsylvania, have invented certain Improvements in Metal-Werking Machines, of which fthe following is a specification.

-(Dur 'nventiQn :relates -to ,metal working .machines of the screw cutting lor threading type, and theohject of lour invention .is :to ,provide .a :machine in which it eis possible -tol Obtain fa vhigzgher perfection ofacc uracy in lthe threading operation than .is ,possible in .theusepf machines of similaror -alliedatype ".8,

I 113. sing yournaled in :suitable bearings 1.8'.

.in use at themresent time.

@ur improved :machine is'eapable of producing lead, powerzand feed screws, worms .fand-.spirals-having single or multiple threads; @ffany length, any diameter, any pitch, and, env style orangleof-.thread 'Itmay also -be= fernployed for the fpurpose of cutting4 ,key-' isc lways or grooves -in shafting, 0f any shape ori length. l The several features -of our ,invention are :more fully ,described hereinafter, referencm being had to the accompanying drawings, -inl which:4

llligfure f1, is e side elevation, partly brokens gaway, of Aa 'metal working .machine embodyling our invention; Fig. 2, .is an enlarged -view in elevation'of 'thecutting end of the@ machine; Fig, 2*,fis al1-enlarged -sectional A\side.elevation of the end-ofthe machine-ep posite the cutting end; Fig. 3, is an enlarged plan viewoflthe cuttingend ofthe machine Fig..ayisranenlargedplanview of the end;

i of ,the machine opposite the cutting end;

Fig. lfyis an enlargedfplan view ofthe een-3 trai `part of ythe Imachine showing the work carrier.; Eig. dnis'an enlarged-side elevati-onf .of -thefendf of the 'machine opposite the cnt- .ting end, 'looking in the direction of ,theY

"arrow :17, Fig". 3"; g-Fig. 55, ,isanelevationbf :the-end ofthe-machine opposite the cutting; `end; "Fig, 6,' is a sectionalfelevation -on z the; line a-a, Fig. 3b; Fig. 7, isa-cross-sectional view on the lline b b, Fig. f3?, and 'Fig. 8, .a sectional view illustrating a detailof-our; finvention. i l

`Powerlto drive the machine mayfbe fur-1 lnished'by amotor 1fandi-s preferably transrnitted through a suitable bac-lqeggearfarrange-g -ment from a pinion 2, on thearmature shaft, 3,ito a gear ,on-e driven lshaftipby the ,use .of asuitable c liein belt 6, ,preferably of .the .silent type. On seidshaft 5., Aa .pair of pulleys, and `8., .are mounted, the pulley 8 rheinglarger than the pulley .7 each .pulley carrying ya clutch, indicated at 9 and 10 re- ,.spectrvely. Disposed between said clutches lisan,expander 1,1, movableonsaid shaft 5, which, when forced 'into engagement with v'the .fingers .12 -of either clutch, clamps' the .latter into engagement with the respective ,pulley which v1s then inoperative driving en- .gegement with said shaft 5. Disposed above `Vtheshafta is a shaft 13, carrying pulleys 14 rend l, `which arebelted-to the pulleys? and beltslgand .17 respectively; the shaft lf ,the expander ll be thrown .into engagernent -W1th .the .clutch of Ithe pulley .8, which .1S .belted .t0 .the smaller ,pulley 15 on said shaft .13, speed deliveredto said drivenshaft d3 will be increased, and,'.vice versa, if the .expander Abe .thrown .int-o engagement with the clutch of .the pulley 7, .which .is belted ,to lthe .pulley 14, .the speed transmittedto' `the .driven-shaft .1 3 .will`.be decreased. It .will V:be noted, therefore, tthat in addition to `the different speeds-.obtainable by Athe use of` 'IEhe shaft L19 is connected torthe shafts 13 The sha t 2O .is .disposed parallel -wit the side of ;the bed plate land is preferably h oused .in bronzefbearings 2 2, suitably car- .r'ledhva bracket 2B havingihubs 2,4, mount- Qn pins25 carried at the side ofthe ma- ,-Q l1ine, This Vshaf t .20 carries a smallK fric- ,tion `wheel ,26 .iniengagement .with a friction 27g-said Wheel 26 being'lreyed to said shaft. 20 land movable with respect .to lSeid friction 'disk 27 -from the centerto the marginofthe latter. "Carried by the rear porltions Vof the Abearings 22, vare 'ears 2 8, in

.Whicha screw shaft 29 is .journaled; saidy ,shaft having aAona-nkhandl'e 30 whereby it.'

rmay be @crateri -as desired. .Upon this` .Shnft29 anu-t 31 is.a`l.'ranged, adapted to be moved longitudinally upon turningl the shaft, and this nut has a bifurcated end with ears 32 in engagement with the friction wheel 26 whereby the latter may be moved between the center and margin of the friction disk 27; said shaft 20 passing through said ears. Ifsthis `friction wheel 26 be advanced from the outer edge of the friction disk toward the center of the same, the speed will be increased. 1t will be seen, therefore, that the speeds of this friction gearing are many, depending upon the diameter of the friction wheel and the diam,- eter of thefriction disk, and the position of the former with respect to said friction disk. Heretofore friction gearing of this type has lacked efficiency because of the 'spring7 inherent in friction disks of large diameter. Ve provide means which, for all practical purposes, o-vercomes this defect. The disk itself is preferablybracedv by ribs 33 on its rear face, and in addition the tailpiece structure is provided vwith suitable housings 34, containing boxes 35, in which rollers 36 are journaled; such rollers being mounted on substantially horizontal spindles and arranged to engage the rear marginal edge of the friction disk 27. By adjusting these parts for proper engagement with said disk, there will be no ten dency of the friction wheel 26 to spring said disk out of its proper plane when in engagement withA the same. Means are preferably provided to set up the boxes 35 and to take up any wear which may occur between the rollers 36 and the friction disk, comprising set screws 37, having lock nuts 38.

In addition to the movement of the friction wheel across the fa'ce of the disk 27, the carrying structure for the same is. arranged to be moved so las to carry saidwheel from and toward the face of the disk so that movement transmitted to the disk may be cut down -at once or stopped entirely should occasion demand, and for this purpose, the friction wheel is under the control of a scr-ew shaft 39 having a suitable crank 40; the carrier having a suitable nut 41 whereby rotation of said screw shaft 39 Vwill move the bracket 23 and the friction wheel 26 from and toward the friction disk.

The use of the small friction Wheel in engagementwith the friction'fldisk is an im. portant feature of our invention, since if anything should be accident-ally placed on the bed plate while the machine is in operation, or if any accident should occur tretard the machinein any way, fthe frition wheel' will slip on the vfriction disk, f iijfop-l ping the feed, without harm toeither', the machine or the blank in the process, of be. ing cut. The friction wheel can be drawn away fromtlie friction disk by means of theY screw and nut described, thereby stopping movement of the friction disk instantly and with it the mechanism controlled by such movement. rlhis can be accomplished with the power on without danger of harming machine or blank.

In cutting a left hand screw, the movable friction .wheel 26 engages the surface of the friction disk 27 opposite the side engaged by it in cutting a right hand screw. If for any reason it be desired to back the screw or other element being cut away from the cutter, the latter may be raised and the friction wheel 26 moved along the splined shaft 20 to the opposite side of the friction disk. If the parts are then set in motion the screw under process of cutting will be turned in a reverse direction.

The friction disk 27 is secured to thc end of a shaft 45 journaled in suitable bearings 46 and extending across the rear of the machine at right angles to the bed plate of the same. At the opposite end of this shaft a removable pinion 47 iscarried, meshing with a removable gear wheel 48, on a worm shaft 49, paralleling said shaft 45 and preferably disposed in the same plane. The removable pinion and gear are preferably secured to the respective shafts by suitable nuts 50 and washers 5l., and by changes in the gear and pinion any ratio of speed may be imparted to the worm shaft 49. The worm shaft carries a pair of right hand worms 52 and 53', the worm 52 being in operative engagement with a pair of worm wheels 54 and 55, while the worm 53 is in operative engagement with a single worm wheel 56.

The worm wheels 55 and 56 are carried at the ends of lead screws 57 and 58, disposed on opposite sides of the bed-plate and paralleling the sanie, while the worm wheel 54 transmits power from the worm shaft 49 to a compound-gearing arrangement,

hereinafter described, for imparting movement t0 a cylinder or sleeve 60 connected and revolving a tube 61 in which the work travels; said tube being connected at its end to a carriage 62, having a work holding chuck 63. It will be seen, therefore, that the use of change gears on the shafts 45 and 49 provides change in speeds fol.` the. lead screws and the compound gear device for revolving the chuck carrying the work. Power may be also increased by the use of change gears on the shafts 45 and 49 with the smaller gear on the shaft 45, and further increase may be secured by reduc ing the size of the worm wheels 55 and 56.

As before noted, power is transmitted to the lead screws 57 and 58 from the worm shaft and worms 55 and 56, While the upper worm wheel 54 transmits power to the chuck 63, carrying the'work, from said worm shaft 49. This worm wheel is keyed to a shaft 65 housed in a suitable bearing f identi" fana-aen 66, andthe pposite and efssad shaft is arranged for the accommodation .of a change erv removablegear whe'el?. i-l i The holow structure ci, carrying the chuck. to 'which` the work is. attached, is

keyed:- tc the sleeve which may besuitably -j'ournaled in a. frame 70' adjacent the .y rear end' of themachine, and carrying gear reducing and compounding means. 'The sleeve (S0-is provided with a; key' 71 engaging a longitudinal groove or. keyway 22y in the hollow member 61 and in order thaty of'lechi'nig' disks 76' at opposite ends of the sleeye, while nuts 77 .at opposite ends beary against thev gear wheels- 74 and-75- carriedl by 'said sleevei The upper portion ofthe frame may carry a seriesl of shafts, in the present in 'stance four', having gear wheels whereby.

different speeds may be obtained. These shafts are indicated at 80, 81, 82 and 83.

At the rear of this frame we provide a; plate pivotally mounted on the shaft 80 and this plate carries a set of` gears receiving movement from the worm wheel 54.

driven by the worm 52, such gears'- being indic'ated :1t-863187 and 88; the latterbeing carried by the aft 80. vAs shown in the accompanying drawings, power is transmitted to the sleeve 60 by means of said. gears 86,. 87 and 88;the latter driving the shaft 80,.'

which has a pinion 90 meshing with a gear wheel 91 on the shaft 81, which in turnl drives a pinion 91a carried Aby said pinionl 91, which pinion 91.l meshes with a gearwheel 92 on the shaft 82, which in turni drives a pinion 93 on the shaft 83. At the opposite end of said shaft 83 a pinion '94 is carried, and this engages' a gear wheel 95 which is in driving engagement with the `gear wheel 7 5 carried' by the sleeve 60.

The power thus transmitted is reduced to such an extent that for every four revolu-f tions of the lead screws one revolution of; the hollow member 61 is produced'by 'said-` sleeve 60, and hence one revolution of the, chuck carrying the work. In the same man1 ner by connecting other gears on said shafts 80, 81, 82 and 83, other speeds and reduc-` tions may be obtained.

shaft of the worm wheel 54-may be provided with a gear wheel meshing directly withthel ygear wheel 74y as shown, or one'of differenti size taking its placa,l both` of said 'wheelsI being of the same vdiameter with the same;

number of'teeth, so that the movement' imscrews, since i' the 'worm wheels 55 and 56 are of the, Same diameter and are driven byworms of the same pitch on the same shaft.

As shown in the plan view, the machine is arranged. togcut right hand threads. To out left hand threads it is only necessary to shift'the position ofv the friction wheel 26 in engagement with the' disk 27 to the opposite side of the shaft 45. It will be understood, offcourse, that right and left hand screws of various pitches may be cut by direct lgearing 'since the gear Wheels of the sleeve .60 are changeable, as are also the gears on the shaft of the worm wheel 54. "In Figs. l; 2 and 3, the cutting end of the machine is illustrated, and the cutter shown therewith receives its motion from the driving shaft 13 in the `following inanner.: At thefront end of 'the machine a pedestal 101 is iXed to the bed plate, and carriesa vertically movable arm 102, which in turn supports vsuitabletransmitting gearing and the cutter 100. The driving shaft 13 imparts motion to a shaft 103 inclined with respect. tothe machine, which in turn drives a shaft104.; suitable universal' coument will` be as free as possible. Meshing with this beveled gear wheel is a bevel pinion 110 4carried by the shaft 104 whereby said bevel gear 107 may be driven. Pivotally -mounted with respect to said arm 102 on the vertical shaft 108, so as to swing in the arc of a circle with respect to said arm andthe bevel wheel 107 carried by -said shaft is a' suitable carrier 111. In the upper part of this carrier a horizontal' shaft 112 is jjournaled, having thereon a bevel pinion 113 in engagement with the bevel gear wheel 107. This frame forms a suitable housing fora pinion 114 carried by said shaft 112, which pinion is in operative engagement' with. an intermediate gear wheel 115 journal'ed in the frame 'or carrier111, and this lf it be desired to reproduce the threads. of the lead screws with-*ifa` direct drive, the..

gear wheel. 115 in turn drives a pinion 116 lcarried by a shaft 117, upon. the inner end of which is mounted the cutter 100, disposed point directly over its center of rotation and the center of-rotation lof its .driving means. The arm .carrying the cutter-is provided,

of course, with the proper scale in order that the angle of cut with respect to the blank may be properly determined. At a point adjacent the cutter we preferably provide a rest or chuck'118 for vthe Work operated upon in order that the same may be given proper support to insure that it will not spring7 under the cutting tool. The machine is shown with a single cutter in the process of cuttin one thread of a double threaded screw,'t e blank having had the irst thread cut therein and the cutter being shown in the act of cutting the second thread. It will be understood, of course,

that we may provide suitable means operated by the screw itself that-will insurethe cutting of the second thread at a point exactly intermediate the rst thread, and that in other instances both threads of a double threaded screw may be cut simultaneously.

We employ a pair of lead screws 57 and 58 for the purpose of moving the carriage 62 having the chuck 63 to which the blank 120 is connected, and movement may be imparted to said carriage by the following means: The lcarriage is provided with a base 122 adapted to the bed plate of the machine, being grooved at 123 for contact with rails 124 on said bed plate, and having overhanging portions 125 carrying bOXes 126 in which rollers 127 are journaled; said rollers underlying projecting edges 128 on said bed plate. The boxes may be held in position by plates 129 secured by bolts 130 and adjusted with respect to the edges 128 by means of set screws "131 adapted to the plates 129.

The carriage may be slotted at 132 above its base for the passage of a double ended lever or yoke 135 pivotally mounted with respect to said carriage on a pin 136, which ma be threaded into the base of the carriage an project through said yoke or lever. At the outer ends of this lever brackets 138 are pivotally-mounted on pins 139 carried by the lever; said Vbrackets having pairs of boxes 14() for engagement with the lead screws, which boxes have threaded hubs 141 disposed in engagement with right and left handed worms 142 and 143 carried by shafts or spindles 144, each of which is provided with a suitable handle 145 or other means at its end whereby the shaft and its worms may be turned to move the boxes 140 into engagement, or withdraw the same from engagement with said lead screws. This construction is very important when employing a pair of lead screws which, for some mechanical reason which may be diiicult to overcome, may not be each of the same pitch or screw length, so that any difference in either one of said screws may be compensated for by the movement of' the main lever 135 `which will impart to the carriage 6 a movement representing the mean between the pitches or thread lengths of the pair of lead screws.

The carriage 62 which we employ is substantially like that shown in the application of Edwin W. Crellin, (assignee of a part interest in the present application) and may be constructed substantially as followsz- Said carriage may be provided with a journal or bearing portion 146, and adapted to such portion is the tubular member 61 having a slight shoulder 147 at one end, which is held in engagement with the carriage by means of locknuts 148, preferably disposed at each end of the same. To provide for free movement of said hollow -member within the journal, we provide thrust bearings comprising disks 149 disposed in concentric rows between annular rings 150; bands 151 being provided to hold said disks in place. At the forward end of the carriage a chuck 63 is coupled thereto; such chuck being carried by a flanged collar 153, and secured thereto by bolts ,154; said collar 153 being threaded onto another flanged collar 155 secured by studs 156 to a member 157, which may be threaded onto the end of said hollow member 61.

In practice, in the use of machines of this character it often happens that the lead or master screw controlling the pitch of the thread and the movement of the work will contract or elongate owing to weather conditions involving changes in temperature.

vThis contraction or elongation for certain size screws is a negligible quantity, but in cutting fine screws of considerable length where accuracy of adjustment is an absolute requirement, it often happens that the contraction or elongation is suiicient to spoil `one end of a screw, and in some instances the entire screw. We therefore propose to provide means for keeping the master screw or the lead screws at a uniform temperature whereby the thread upon the same may be uniform from end to end, and further to provide means for increasing or decreasing this temperature whereby we are enabled to elongate or shorten the lead or master screws to such an extent as to obtain variations in the pitch of a screw being cut, that are not possible to obtain with any practicable arrangement of measuring devices. To this end the master or lead screws 57 and 58 are made hollow and means may be provided for introducing a fluid medium thereto which mayhave the effect of maintaining the same at the same temperature at all seasons of the year, therebyl maintainin their own pitch in the proper condition or reproduction, or of increasing or decreasing the temperature to such a degree as to elongate or shorten said master or, lead screws to an extent suiiicient to insure the cutting of the new thread with a pitch of an odd dimension. To eect this the following mecha- 130 4 tatiana nism may 'be employed: The lead screws-mt the `rear end of the machine'lnay be bolted and keyed to the worm wheels '55 iand 56. On each side and formed Vas xpart df the worm wheels are osets turned to rrevolve :in suitable bearings 161. 'The lead screws are reduced at 162 so as to Vbe accommodated in stuilng boxes 163 .providing tight connections for the lead screws and yet permitting proper movement of .the screws when they are turned. The lead screws may be held lto the worm wheels by Anuts 1164 Aand 165 and the ends of the lead screws may have removable collars or rings 166 surrounded by -packing 167 which may be en' aged by plugs 168 carried bythe frame and ttn-g the boxes 163. rdll/lese boxes ymay be held against l'nloven'ie'nt by nuts 169.-

At their forward ends the lead screws Iare journaled in suitable boxes 170 carried by brackets 171 which 'may be secured to the sides of the machine, and these boxes may have movable .glands 172 at the `end connected direct-ly to the screws so that longitudinal movement of said screws will be imparted tosaid glands. These glands lmay be suitably connected 'to tubes 173 through which iuid or liquid Aof vary-ing `degrees of temperature may be passed when it is 'de-- sired to maintain .the screw at va substantially uniform length, or when it is `desir-'edf fto raise the temperature ,of 'the same tov Ilengthen it, or to lower the temperature of;

the same with a vview o'fshortening either or both 'of said screws. The gboxes receiving 'the i gland may te hollow at the point 1.7i far! the reception of springs I178 tending Ito maintain the parts normally in proper position prior to the introduction of'a cooling or 'heating Huid. These boxes :rnfay also be provided .with scales 'or indicators 4corn-prising-afse'gmental plate 180, with anarrow 181 -pivoted thereto at 182,1and provided with a spring 1.83 whereby it maybe Akept normally l in 'its proper position; said 'arrow having fan if ann 184 which may lie in engagement with@ a recess 185 formed in the gland, so th'atl movement -of the latter will 'be .transmittedgl to said farm 'and thence t'o |-the arrctv whereby the extent of 'movement may be fdeinitely ascertained. .ln some instancesit `may be? desirable-to definitely regulate the-'extent of movernent, andthis may be xaccomplished "by having #a thermostaitic control for fthe ya'lvesi supplying the -heating or eo'olingmedium which may v"be set to insure the delivery of 'a fluid fait a predetermined temperature, which temperature will be Inai'ntaifned irrespective yof latmospheric conditions.

'llh'e arm 1'02 projecting from the pedestal 101 and carrying the cutting 'elementoverhangs the werk. Toprevent vibration "o'f `said arm while 'the cutter is in contact with fand operating "on the blank, we provide supparting means fer said 102 lapposite the Hpeestal i101..y This supporting means cUmpnises-a o'olu'mn for post 190, carried vby a bracketzlQlLseoured to the side of the 'bed plate, and such post4 may have its end reduced to `fita socket lin said'brackea 'being .retained therein bya nut 192. The arm 102 has' la .clamping .pdrtion 193 embracing the post 190, with jawscarrying a screw mem- .then locked to tle post 190 rby the 'screw member 1'94.

We claim:

.11 In 7a metal *working machine adapted -fdr .cutting screw threads, the f'combination 'of :a bed-plate, fa carriage lmovable thereon, a sleeve rotatably mounted in said carriage andfadapted rto carry a blank -to be cut, a plurality olf master screws in operative engagement with said carriage, means for 'turni-ng said screws to move fthe carriage, 'means connecting thescrews to the fc'arrrage and 'serving to compensate for-the pitch -difterences of said screws, means for turning said Sleeve .Simultaneously with its Elongitudin-al movement, and 'a cutter' for 'operating lIon said blank.

2; In a metal working machine adapted Ifor 'cutting screw threads, the 'combination of a :bed-plate, -a carriage thereon, :a sleeve rotatably mounted in said lcarriage and adapted ito carry a blank to Ib'e vcut, a plu` ralifty iof masterfsorews inoperative 'en-gagement `with said carriage, means for turning said 'screws to move the carriage, a connection between said screws and carriage 'scriv- -ing'fto compensate for the lpitch dorences 'of said screws, land 'a cutter 'for operating en said blank. 4

3. Ina @metal working machine adapted for llmrttiiag screw threads, the combination elf a bedplnlte, a carriage movalblethereon,

a hollow sleeve rotatably mounted lin `said 'carriage and adapted to carry a 'blank to 'be out, fa plurality foff master screws, means `fior i coupling said screws to tthev carriage and 'serving to compensate for the pitch ditl'er- :ences tof said screws, a cutter 'for operating said blank, an adjustable carrier there- 'forand means for operatin'g 'said cutter.

4. in a metall Workin machine adapted for cutting screw fthrea s, fthe Imnnbnation of a bedplafte, fa carriage mcafable thereon, a hollow 'sleevev'rotatably momrted in 'said carriage andfaapted to 'carryablank to be cut, a'plurality of master screws, 4means 'for coupling said 'screws 't'o the 'c'an'iage and .Serf-ving 'to compensate for the1V pitch dier-A,

ences of said screws, means for independently connecting said screws with said carriage, a cutter for operating on said blank, and means for operating said cutter.

5. In a metal working machine adapted for cutting screw threads, the combination of a bed plate, a carriage movable thereon,

a rotatable sleeve mountedin said carriage,

, a chuck carried by said carriage for receiving the blank to be cut, a plurality of master screws, and means operatively connecting said master screws to the carriage, said means serving also for compensating any diiference in pitch in said lead screws in the 3 5 transmission of their rotative movement to impart longitudinal movement to the carriage.

v 6. In a metal working machine. adapted for cutting screw threads, the combination of a bed plate, a carriage movable thereon,

a rotatable sleeve mounted in said carriage,

a chuck coupled to said carriage for receiving a blank to be cut, a plurality of masterl screws, a cross-piece pivoted to the carriage, separable nuts carried by said cross-piece for engagement with said screws, and a cutter for operating on said blank.

7. The combination, in a metal working machine adapted for cutting screw threads, of a movable carriage, a rotatable sleeve mounted therein, a pair of lead screws, and means pivotally mounted on said carriage to which said lead screws are coupled whereby said carriage may be driven by the lead screws.

8. The combination, in a metal working machine ada ted for cutting screw threads,

of a movab e carriage, a rotatable sleeve mounted therein, a pair of lead screws, a

cross-piece pivoted to said carriage, and nuts pivoted to said cross-piece and in engagement with the lead screws whereby said carria-ge may be driven by the lead screws.

9. The combination with a metal working "a5, machine of the screw cutting type, of a hollow member, a sleeve in driving connection with said hollow member through which it vmay be moved, a carriage to which one end of said hollow member is coupled, a plurality of lead screws, a cross-piece pivotally V connected with the carriage, and adjustable means operatively connecting said crosspiece with the lead screws.

10. The combination with a metal working machine of the screw cutting type, of a vhollow member, a sleeve in driving engagement with said hollow member through which it maybe moved, a movable carriage Acoupled to one end of said hollow member,

6o a plurality of lead screws, a cross-piece,

separable nuts pivoted to said cross-piece and in operative engagement with said lead screws, and la pivotal connection between said cross-piece and the carriage.

- 11. In a metal working machine of the screw cutting type, 'the combination of a frame or support, a blank carrier, driving means for said carrier including a friction wheel, a friction disk in engagement therewith, supporting means for the marginal edge of said friction Wheel whereby the same is prevented from springing, said supporting means being disposed on opposite sides, means for adjusting said supporting means, a pair of lead screws, and means for transmitting movement of said friction disk to said lead screws.

12. In a metal working machine of the screw cutting type, the combination of a frame or support, a blank carrier, driving means for said carrier including a friction wheel, a friction disk in engagement therewith, means for adjusting said friction wheel, means for adjusting the friction disk,

a support for the marginal edge of said g5 friction wheel whereby the same is prevented from springing, a pair of lead screws, and means for transmitting movement of said friction disk to said lead screws.

13. In a screw thread cutting machine, the combination of a blank carrier, a pair of hollow lead screws, means'for driving said screws, means for transmitting the movement of said screws to said blank carrier whereby the blank may be rotated and simultaneously moved longitudinally, stuffing-boxes carried by said lead screws,means .for delivering fluid to the interior of said lead screws to alter the temperature of the same and effect changes in their length, and means for taking up changes in the length of said lead screws whereby a proper working position may be maintained.

14. In a screw thread cutting machine, the combination of a hollow lead screw, means for delivering a temperature controlling fluid to the interior of said screw, means for ascertaining changes in the length of said screw, and means for taking up the changes in the length of said screw whereby. a proper working position may be maintained.- l

15. In a screw thread cutting machina the combination of a blank carrier, a hollow lead screw, means for driving said screw, 1mi

means for transmitting movement from said screw to the blank carrier, stui/ng- Y boxes at the endsof said screw, means for delivering a temperature controlling iuid to the interior of said screw, means for 120 ascertaining the changes in the length of said screw, and means or taking up changes in the length ofsaid screw whereby a proper working position may be maintained.

16. In a screw thread cutting machine, the combination of a blank carrier, a hollow lead screw, means for driving said screw, means for transmitting movement from said screw to the blank carrier, stuiing boxes at each end of said screw, means for 13o tained at all times.

y17. In a screw thread cutting machine, the combination of a blank carrier, hollow lead screws, means for driving said screws, means for transmitting movementl from said screws to the blankcarrier, stuffing boxes at each end of said screws, means for delivering temperature controlling fluid to the interior of said screws to effect changes in their length, means for ascertaining changesy lthe blank carrier, a second worm wheel driven by the worm shaft and disposed above one of the lead screws, and means for transmitting movement from said second worm wheel to the gear wheel of the blank carrier. f

19. The combination, in a metal Working machine of the screw cutting type, ofv a blank carrier, lead screws, a vworm shaft,

'worm wheels on said lead screws in engagement with said worm shaft, a gear wheel on the blank carrier, a second worm wheel driven by the worm shaft and disposed above oneof the lead screws, means for transmitting movement from said second worm wheel to the gear wheel of the blank carrier, and reducing gearing interposed be- 'tween said second worm wheel and the gear wheel of the blank carrier.

20. n a metal working machine of the screw thread cutting type, the combination of a bed-plate, a carriage movable thereon, a sleeve rotatably mounted in said carriage and adapted'to carry a blank to be cut, a plurality of master screws, adjustable means connecting said screws in operative engage ment with` said carriage, said means also serving to compensate for the pitch differences of said screws, means for transmittin longitudinal and rotative movement to sai carriage, a cutter for operating on said blank, and means for driving the sleeve and cutter from the same source, of power.

In testimony whereof, we have signed our names to this specification, in the presence of two subscribing witnesses.

JAMES R. oRELLIN. THOMAS R. oRELLrN.

`Witnesses:

MURRAY C, BOYER, Jos. KLEIN. 

